Natural Gas Line Question

I have a question about specifics regarding underground natural gas line piping. Once the ground thaws, I will be treching from my outdoor brewery to my house to connect in to the natural gas line. I will "assist" with the process but most likely will not do the work myself on this one.

I would, however, like to limit the amount of labor involved by preparing the trench and anything else that may be needed. I have a couple of options for the process. The closest source for my run would be at the back of my house. I have a pipe stubbed out from the back of my house (in the wall) for a NG BBQ. I could trench to the area and core drill under the house to gain access to the pipe. There is plenty of room to work underneath my house. My only concern is connecting into a NG underneath my house. The idea of any possible leaks concerns me.

Option B would be treching over to the side of the house where the meter is. This is around 50 - 60 extra feet. Can this be "split" at the meter prior to where it is piped through the wall? My thought would be splitting at the meter and running straight down outside the wall and into the trench. Of cource, what I have learned is what seems logical isn't always code. The only reason I like the "outdoor" idea is there is nothing new being run underneath my house.

Anyone have experience with this?

If it were me I would stay outside (although, with proper fitting pipe and a pressure test you can be sure of no leaks you would be fine inside). I would measure the trench length and contact the gas company and ask for 2 steel to plastic risers and have them use 3/4" MDPE plastic pipe to connect/fuse them. You could lay the pressure tested risers and pipe in the ground back fill and just hire a plumber to make the final tie behind the meter. This would also give you a shut-off on both ends. In my area the gas company uses contractors to run the gas services, these guys can build you what you need and leave the trenching and back fill up to you which would be the most intrusive and expensive portion of work. Good luck.

Making a connection under your house is easy and safe as long as you seal the threads properly and then leak check your work when done. If you don't have the confidence that you can do it without the joints leaking, get someone who is qualified. It's a very simple and straightforward procedure.

I would run the line from the meter. Reason being, you will have an additional shut off going to another building in case of an emergency.
You will also have to run a larger line (depending on length ) for volume. (like a pool heater).

sigmund said:

Making a connection under your house is easy and safe as long as you seal the threads properly and then leak check your work when done. If you don't have the confidence that you can do it without the joints leaking, get someone who is qualified. It's a very simple and straightforward procedure.

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I agree with this, no reason to be scared of another NG connection under your house. Mercaptan, is a chemical added to natural gas to give it a horrible smell, if you have a serious leak, you'll know it long before it causes any danger of explosion. In order for NG to flash, it has to be mixed in a specific concentration with outside air, the point at which it can flash is called the LEL, or lower explosive limit. For NG this is about 6%, pretty difficult to get that high outdoors, or even under a house with so little pressure.

You can place a shut off where it comes out of the house? If not be sure and put another valve at the end of the line somewhere before it connects to your brewing equpment. After 8 years in the natural gas driling/completion business, I've learned you can never have too many valves in a line. Another thing to consider, going to your meter means more pipe, means more chances of a leak, all that is simple is good.

I was faced with almost exactly this same decision when building my garage. Either tie into the existing line in my basement closest to the garage site, or dig a whole seperate trench much further, around the house to the meter. As others have said, as long as you are careful with your connections and thoroughly leak test the line, making natural gas piping connections is actually quite easy and safe. I opted to connect through the house and have been very happy with the results.

Residential natural gas downstream of the meter runs at very low pressure (usually well under 1psi), so it's actually pretty forgiving to work with.. much easier than water even which runs at 30-80psi in my City. Obviously the risk is much much higher with gas, so you don't want to get complacent and cut corners. Once you connect up your line you'll want to pressurize it with air to 15psi and ensure it holds steady for 24 hours and do lots of soapy water tests . But as you can see there is a built in margin of error there.

EDIT: I should also mention the city an county inspectors both took a look at what we did and had absolutely no problems with it.

No one has mentioned gas pipe capacity. The pipe needs to be sized to serve your brewing equipment as well as the additional appliances connected to the line. Your house service that you have in the basement may nit have enough capacity to run your gas stove, furnace, and water heater along with your brewing set up. This could result in one or more appliances not operating correctly when they happen to run concurrently. I would strongly advise having a qualified person size the service using the national fuel gas code standards.

I wouldn't even bother with the NG BBQ stubout unless you can verify that it's at least 3/4" pipe. The biggest I've ever seen for this purpose is 3/8" and that's because BBQs are typically under 40kBTU running all out. I don't have all the calculations in front of me, but the longer the run is, the larger it has to be due to frictional losses. I don't know if 3/4" would even cut it.

I agree with both of the above comments. Capacity is a critical factor. I should have mentioned that the line I was able to connect to in my basement was a 1" supply. From there we ran 3/4" to the garage (~50'). I chose to step it down here so as not to starve my upstream appliances of gas when I'm brewing. It's plenty for me, but I could see how going even bigger throughout would be better if I was doing 1bbl batches, or similar.

If you have a crawl space under your house, you should be able to run black iron pipe attached to the floor joists to the edge of footers. Then run this via a riser to a trench, and I believe this would be within code in most places. Once at the trench, the typical pipe underground would be yellow polyethylene (PE), and then back up to the outlet via another coated iron riser. We recently had to replace our gas line to our pool heater, and it was done this way, including permit and inspection. BTW, one estimate I received was for over $10K to do this! It was a pretty long run (about 150 feet), but I still laughed in this guy's face. I ended up hiring some handymen to dig the trench for $500 and another $1200 for a different plumber to run the PE and risers, and then do a pressure test. BTW, this was 1 1/2" all the way, but is connected to a 400K BTU pool heater and my BBQ island. If you are going to the trouble, you should at least run 3/4 or better yet, 1" pipe.

Great responses. I never gave any thought to how many appliances were upstream of the same line. My house has a gas furnace and water heater. THe BBQ port is not used yet. My home is two stories and the gas furnace is located in the second floor attic. The water heater is near the garage. My guess would be the gas water heater would end up being upstream. It also stimulated thought as to what the size of the piping is for the BBQ gas lines.

10K is much more than I would ever dream of spending. In fact, so is $1700. I already installed the gas piping inside the shop and pressure tests it during inspection. I am capable of running the gas pipe in the trech so maybe this is also an option. I could always pressure test my work at both ends and then let a plumber complete the inspection.

The shop will have a NG water heater and burner for brewing. Is this something that would cause issue with what is upstream? I imagine my burner will be around 65000 btu.

I honestly don't think supply is an issue here. If the rest of your house is sized correctly and using everything in the house and the bbq grill at the same time is not an issue you should be ok. I'm over simplifying this but a good rule of thumb is for every cubic foot you can get about 1,000 BTUs, the length of pipe makes a big difference though. My guess is a 3/4 line with full regulator pressure is going to bring you about 325 cubic feet, even if that drops in half over the distance your talking about, (which it won't), your still going to have way more than you need. Obviously I can't see how everything under your house is connected, and I don't know what demand you have in your house, or what size pipe is coming from your meter, so this is just some general guestimating.

Make sure you use full port valves. Cheap Chinese knock offs may be 1" but the port can be as little as 1". If your running black pipe be sure to tar it. If running flexible I would install in PVC tubing. Add up your total BTUs in the house and calculate line size. Mor than likely you will be fine as long as you come off the 1" line coming into your house. Possibly larger depending on whats in your house but 1" is pretty common if house is sized right and proper appliances installed.